The monitoring of the condition of elderly people in various environments is indispensable if it is desired to respond to the growing proportion of the population that is ageing. Presented in the art are various means for monitoring sick people or other people needing care, both in home surroundings and in institutional care. For example, over the course of time many types of monitoring means have been used in hospitals for arranging the monitoring of patients.
Bed sensors form one type of sensor related to monitoring the state of people. Presented in the art, for example, are bed sensors with which the presence of a person in bed can be measured by means of a pressure sensor that is placed on the bed in such a way that it detects the weight of a person when the person is lying in bed.
Also known in the art is to use sensors to be installed on the floor, or under it, that detect the presence and movements of people by means of capacitive sensors or sensors based on pressure, and by means of this data to deduce whether a person needing monitoring is in bed or has gone somewhere else.
Not presented in the art, however, is a type of sensor that could reliably measure with one and the same sensor the presence of a person in bed, his/her departure from the bed and whether the bed has become wet, e.g. as a consequence of sweating, urine or other secretion.